Bag of paper or like material and the manufacture thereof



1mm H, Wu J. c. HELLEMA BAG OF PAPER OR LIKE MATERIAL AND THE MANUFACTURE THEREOF Filed March 31, 1958 Ian Cornehs R yNvE N-FQK Q1 mm k fi A i Patented June 11, 1940 OFFICE BAG OF PAPER R LIKE-MATERIAL AND THE THEREOF Jan C'ornelis Hellenia, Zaandam,

assignor to N. V. Geln's. Hellema,

Netherlands,

Papierwarenfabrik Voorheen Zaandam, Netherlands, a

- company of the Netherlands Application March 31, 1938,Serial Intlie Netherlands January 31, 1938 1 Claim. (Cl. 229-61 The present invention relates to bags of paper or like material, which may be coated or impregnated or otherwise treated as may be required, and which for brevity will be referred to as paper.

5 The invention relates particularly to that kind of paper bag which although folding flat, has a rectangular cross section and aflat bottom when in use. Such bags hitherto have consisted in essence in a single piece or strip of paper, with the longitudinal edges thereof stuck together forming in effect a tube one end of which having been cut; folded and stuck in certain ways to form the bottom. Production in quantity, for

example by a continuous mechanical method, is

very complicated and requires, particularly for the formation of the bottom a complicated mechanism that is not sufliciently reliable and fr'equently gives rise to interruptions in the operation of bag making. Moreover the bags when produced have the disadvantage that before they can be filled they have to be opened or extended by hand, or even by the very insanltary method of blowing into them. The present invention seeks to provide a construction of bag and a method of manufacture dimculties.

According to the primary feature of the invention, a paper bag of the kind mentioned, i. e., having a substantially rectangular cross section when open and a fiat bottom, has seams (prefer-' ably secured by adhesive)- along two opposite side walls, and a seamless bottom. Such a bag preferably consists of a blank, which may be a section of strip or like paper, which is doubled upon itself about a transverse fold or a plurality of transverse folds, the longitudinal margins also having folds to form front and back, and opposed side, walls respectively, the side walls each being formed by two parts integral with the front and back walls, and united along a seam. Further constructional features, somewhat dimcult to discuss without reference to drawing, are included within the invention, as will be made clear hereinafter. f

Further according to the invention, a method of manufacturing paper bags characterised as above, consists in forming a substantially rectanheight of the desired bag when in use, folding it upon itself about one or more transverse lines simultaneously or previously folding in the longitudinal sides so that opposed sides come edge to edge and uniting such e'dgespreferably by adhesive. a

Further details of the novel method will bethereof, avoiding these come clear from; the following description of the invention with reference to the accompanying drawing.

Fig'. 1 is a perspective view of a paper bag according to to the invention in which the front wall is partially cut away.

Fig. 2 shows perspectively a bag according to the invention in one of the stages of its production, viz. shortly before gluing thegumming strip or strips of one half of the blank to the folded 10 longitudinal marginal portions of the other half, after doubling the blank upon itself.

Fig. 3 is a plan view of a blank for the production of a bag as shown in Fig. i.

Fig. 4 illustrates perspectively the initial fold- 15 mg of the blank. 1

As appears from Fig. 1 the bag in opened or extended condition has a substantially rectangular cross-section; the two opposite narrow sidewalls I and 2 of the bag, along each of which runs 20 a gummed seam I 2 adjacent the integral bottom 3 are folded inwardly to form triangular pockets 4 and 5 respectively. The lower walls of such triangular pockets are glued to the bottom of the bag as will appear from the following de- 26 as shown in Fig. 3 or. preferably, with a continu- 80 'lines" Ill, ll running Ill, are glued on to ous paper web of which sections are cut off, of a lengthgreater than twice the height .of the bag when in use. Of this section, along the longitudinal sides thereof, and if desired before severing the section from the web', strips are cut off along 35 half the length of the section in such a manner thatalong the other half length there remain laterally projecting gumming strips-6,1, which subsequently are folded outwardly along the lines 8, 9. -.As will be readily understood such gum- 40 ming strips may also be disposed in stepped relation instead of directly opposite .each other. From the blank thus obtained the longitudinal portions are subsequently folded inwards about parallel to the longitudinal 5 edges and equidistant therefrom, the triangular regions l2, l3 being previously coatedwith an adhesive so that these regions during the folding of the longitudinal portions M, I5 about'the lines the middle region or bot- 5 tom IE or the blank. The gumming strips 6, l are thereby presented towards the opposite longitudinal portions H5, all in the manner as shown in Fig. 2. ,The portions of the centre region l6 coming into-contact with the regions I2,

hesive is applied.

.In this condition of the transverse lines of oizeakness'll, "(and I9 re,- spectively, are formed in the blank, of which the first is located "in the middle of the blank, the remaining two being spaced from'said centre line a distance equal to the width of the longitudinal portions l4, l5. Subsequently, the inclined lines of weakness 20,.21 vandi22, 23 are formed, such.

lines diverging symmetrically from the two'ends of the centre transverse line H and rlmning to-the points defined by the intersection ,of the lines Ill and ll'with the two other transverse lines l8, l9. These inclined lines of weakness therefore enclose together with the'corresponding portion of the longitudinal lines of weakness III, II, the said triangular regions l2, l3. It will be apparent that the lines of weakness Ill-43 may be formed prior to the hesive.

After the folding of the longitudinal portions I4, 15 and the gluing ofrthe triangular regions l2, l3, on to the centre region IS, the blank in the manner shown in Fig. 2 is folded upon itself about the centre transverse line of weakness l1 and thegumming strips coated with adhesive are glued, or are otherwise fixed, against the opposite marginal portions l4,

15, thereby completing the bag. The above described series of operations may be carried into effect by the aid of very simple mechanical means. I

A bag thus produced will immediately tendoto set itself upon a fiat bottom under the pressure of material poured thereinto, in so doing opening itself about the lines of weakness l8, l9 and the automatically takes so that the bag up the substantially rectangular cross-sectional formation.

When starting with a blank as shown in Fig. 3 the particular face of the gumming strips 6, I and the-edges of the marginal portion. l4, l5 contactinclined lines of. weakness 20-23,

blank, three parallel application of ad- 6, I previously bein 2,203,726 13, may alternatively be those to which the ading such strips as also the triangular fields l2, l3 and the corresponding portions of the centre field l6 may be covered with a rubber solution so that such portions, when brought into contact with each other, are stuck together, .whilst they will not stick to surfaces not covered with such solution, so that the blanks may be stacked flat without risk. 1

It will be understood that the invention is not limited to the precise embodiment above described and illustrated in the accompanying drawing, and in particular that the sequence of the various manipulations in making the bag, may be varied at will.

What I claim is:

A collapsible bag of paper or the like forming in open condition a rectangular casing having a flat one-piece bottom and outwardly open triangular pockets adjacent said bottom, said bag comprising in collapsed condition a front and 'a rear panel integral with and folded upon one an- .other about a transverse center fold, and two side provided with two oblique creases running diagonally from the point where thetransverse and longitudinal center folds meet to the pomts where the transverse creases intersect the longitudinal edges of the side panel, the two contiguous triangular portions of each side panel defined by said oblique creases, the panel edges and the transverse center fold being adhered to the inner faces of said front and rear panels, re- "a spectively'. JAN CORNELIS HELLEMA.

center fold, all said 

